At the top of descent; at FL360; both throttles retarded to idle. At that point; the duct pressure on both engines fell to less than 10 psi; on both engines. The cabin altitude started to rise. The pressurization panel was first placed in standby; which had no corrective action. The cabin did exceed 10000 ft. The QRH for intermittent cabin altitude warning horn was called for and run. The pressurization panel was then placed in manual AC; and the outflow was closed and cabin altitude control was regained at about 10500 ft. All the while; the plane was being descended to an asked for given clearance of 10000 ft. Cabin altitude in manual AC was controled to about 5200 ft; in preparation for landing. Cabin pressure was controled the rest of the flight; which was about 25 more mins. Uneventful approach and landing was made by the captain.

Narrative: AT THE TOP OF DSCNT; AT FL360; BOTH THROTTLES RETARDED TO IDLE. AT THAT POINT; THE DUCT PRESSURE ON BOTH ENGS FELL TO LESS THAN 10 PSI; ON BOTH ENGS. THE CABIN ALT STARTED TO RISE. THE PRESSURIZATION PANEL WAS FIRST PLACED IN STANDBY; WHICH HAD NO CORRECTIVE ACTION. THE CABIN DID EXCEED 10000 FT. THE QRH FOR INTERMITTENT CABIN ALT WARNING HORN WAS CALLED FOR AND RUN. THE PRESSURIZATION PANEL WAS THEN PLACED IN MANUAL AC; AND THE OUTFLOW WAS CLOSED AND CABIN ALT CTL WAS REGAINED AT ABOUT 10500 FT. ALL THE WHILE; THE PLANE WAS BEING DSNDED TO AN ASKED FOR GIVEN CLRNC OF 10000 FT. CABIN ALT IN MANUAL AC WAS CTLED TO ABOUT 5200 FT; IN PREPARATION FOR LNDG. CABIN PRESSURE WAS CTLED THE REST OF THE FLT; WHICH WAS ABOUT 25 MORE MINS. UNEVENTFUL APCH AND LNDG WAS MADE BY THE CAPT.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.